Urinary tract infection etiology pathagenesis management

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1. Urinary tract infection Dr indra Yadav

2. Infection of urinary tract system

3. Urine Examination Routine Physical and Chemical Examination Microscopic Examination of cells, casts, crystals and microorganisms Special Examination

4. Collecting Sample Avoid strenuous physical activities in the hours preceding collection Menstruation Washing hands, external genitalia should be wiped with clean wet paper towels, spreading the labia in females and retracting the foreskin in males Mid stream urine Volume 50ml Sample should be examined within 1hr of collection

5. Physical Examination Color Pale – Dark Yellow – Amber (depending upon the level of Urobilin) Dark yellow – Brown (Jaundice) Changes to dark color upon standing Porphyria (Porphobilinogen), melanoma (Melanogen), Alkaptonuria (Homogenistic acid) White – Chyluria Drugs Rifampicin- Red Nitrofurantoin- Brown, Levodopa -Black Amitryptiline -Blue green, Imipenem Brown

6. pH Turbidity Leucocytes,erythrocytes,bacteria,crystals,contaminations,chyluria can cause turbid urine Odors Pungent – UTI Specific gravity Normal value range from 1.010 to 1.030 <1.010: Hyposthenuria – Diabete

7. Chemical Features Leucocyte Esterase(LE) The LE test dipsticks detects esterase, an enzyme released by white blood cells A positive test results from the presence of white blood cells either as whole cells or as lysed cells Pyuria can be detected even if the urine sample contains damaged or lysed WBCs

8. Chemical Features Nitrite Bacteria in urine reduces nitrates to nitrites (Enterobactericae) Positive dipstick test indicates presence of bacteria in urine

9. Microscopic Examination Before microscopic examination pH and osmolality (Specific gravity) of urine should be considered Alkaline urine causes decrease casts and WBC tends to lyse Decreased osmolality causes lysis of WBC and RBC

10. Cells Red Blood Cells: Hematuria is defined as 2 – 5 RBCs/HPF A single urinalysis with hematuria = menstruation, viral illness, allergy, exercise, or mild trauma. Persistent or significant hematuria = >3 RBCs/HPF on three urinalyses or a single urinalysis with >100 RBCs or gross hematuria

11. Cells White Blood Cells "Pyuria" is usually defined as 10 or more leukocytes per HPF in a centrifuged specimen or 5 or more when uncentrifuged Represents infectious or inflammatory process e.g. UTI, Parenchymal infections, Acute proliferative glomerulonephritis Sterile pyuria (positive leukocytes, negative culture) may occur in partially treated bacterial UTIs, viral infections, renal tuberculosis, renal abscess, UTI in the presence of urinary obstruction, urethritis as a consequence of a sexually transmitted infection, inflammation near the ureter or bladder (appendicitis, Crohn disease), or interstitial nephritis (eosinophils).

12. Microorganism Bacteria: UTI, contamination Fungi: Candida most common Contamination from genitalia DM, prolonged catheterisation, immunosuppresion Protozoa: Trichomonas vaginalis Contaminated from genitalia Parasites: eggs of Schistosoma hematobium

13. Terminology Recurrent UTI Three or more uncomplicated UTIs in 12 months is used to define recurrent uncomplicated UTI. Recurrent UTIs may be due to bacterial reinfection or bacterial relapse. RELAPSE A relapse occurs when the same organism is not eradicated from the urine after 2 weeks despite appropriate antimicrobial treatment. REINFECTION Reinfection occurs when recurrence presents with a different organism, or with the same organism greater than 2 weeks after the initial infection, or if a sterile culture is documented between the 2 UTIs in a patient who is no longer taking antibiotics COMPLICATED UTI A UTI is generally considered complicated if the patient has an anatomic abnormality, a voiding dysfunction, or an obstructed urinary tract, or if the infection is iatrogenic.

14. RISK FACTOR FOR RECURRENT UTI Any spermicide use within the previous year, especially if used with a diaphragm Atrophic vaginitis Chronic diarrhea Cystocele First UTI when young (prior to 16 years of age) Genetic predisposition (usually through bacterial/vaginal mucosal adherence factors) Higher frequency of sexual intercourse Increased post-void residual urine (incomplete bladder emptying) Inadequate fluid intake (low urinary volumes) New or multiple sexual partners Mother with a history of frequent or multiple UTIs Urinary incontinence Use of spermicide coated condoms

15. Treatment Single dose treatment Amoxicilln 3g Ampicillin 2g Cephalosporin 2g Nitrofurantoin 200mg Trimethoprim sulfamethoxazole 320/1600mg

16. 3 days course Amoxicillin 500mg three time daily Ampicillin 250mg four times daily Cephalosporin 250 mg twice daily Ciprofloxacin 250 mg twice daily Levofloxacin 250 mg or 500 mg daily Nitrofuratoin 50 to100mg four time daily or 100 mg twice daily Trimethoprim-sulfamethoxazole 160/800mg two times daily

17. Other Nitrofuratoin 100mg po four times for 10 days Nitrofuratoin 100mg po twice times for 5 to 7days Nitrofuratoin 100mg po bedtime for 10 days

18. Diagnosis of recurrent uncomplicated UTI Clinical diagnosis of each UTI episode is supported by symptoms of dysuria, frequency, urgency, hematuria, back pain, self-diagnosis of UTI, nocturia, costovertebral tenderness and the absence of vaginal discharge or irritation Complicated causes of UTI may also be ruled out on history and physical examination. Uroflowmetry and determining post void residual are optional tests in post-menopausal women to exclude complicated causes of UTI Culture and sensitivity analysis should be performed when symptomatic and in 2 weeks from sensitivity-adjusted treatment to confirm UTI, guide further treatment and exclude persistence.

19. INVESTIGATION Urine routine and microscopy culture and sensitivity Cystoscopy and imaging for complicated UTI limiting spermicide use Cranberry extract Post coital antibiotics prophylaxsis Self-start antibiotic therapy with a 3-day treatment dose antibiotic at the onset of symptoms Vaginal estrogen creams or rings  Prophylactic measures against recurrent uncomplicated UTI